How to treat Lactobacillus (lactic acid bacteria) in urine, specifically a urinary tract infection (UTI)?

Treatment of Lactobacillus in Urine (UTI)

Lactobacillus in urine does not typically require antimicrobial treatment as it is often considered asymptomatic bacteriuria (ASB), which should not be treated in most patient populations according to current guidelines.

Understanding Lactobacillus in Urine

• Lactobacillus is generally considered a commensal organism and may represent contamination from the vaginal flora in women
• When found in urine cultures, Lactobacillus rarely represents true infection requiring treatment
• Current guidelines strongly recommend against screening for or treating ASB in most populations 1

When NOT to Treat Lactobacillus in Urine

Strong recommendations against treatment exist for the following groups 1:

• Women without risk factors
• Patients with well-regulated diabetes mellitus
• Postmenopausal women
• Elderly institutionalized patients
• Patients with dysfunctional/reconstructed lower urinary tract
• Renal transplant recipients
• Patients before arthroplasty surgery
• Patients with recurrent UTIs
• Patients with spinal cord injury
• Patients with short-term or long-term indwelling catheters

When to Consider Treatment

Treatment should be considered only in specific circumstances:

1. Pregnant women: Screen for and treat ASB in pregnant women with standard short-course therapy or single-dose fosfomycin trometamol (weak recommendation) 1

2. Before urological procedures: Screen for and treat ASB before urological procedures breaching the mucosa (strong recommendation) 1

3. Symptomatic infection: If the patient has symptoms of UTI (dysuria, frequency, urgency) and Lactobacillus is the only organism isolated in significant quantities, consider treatment based on susceptibility testing 2

Treatment Options When Indicated

If treatment is indicated based on the above criteria, consider:

1. First-line options 2:

   • Fluoroquinolones (levofloxacin or ciprofloxacin) for 5-7 days
   • Nitrofurantoin (except in cases of pyelonephritis)
   • Trimethoprim-sulfamethoxazole (based on local resistance patterns)

2. Alternative options:

   • Fosfomycin 3g single dose (particularly effective against resistant organisms) 2
   • Cephalosporins (based on susceptibility)
   • Amoxicillin plus clavulanic acid (based on susceptibility)

Prevention of Recurrent UTIs

For patients with recurrent UTIs where Lactobacillus has been isolated:

• Vaginal estrogen replacement for postmenopausal women (strong recommendation) 2
• Methenamine hippurate for women without urinary tract abnormalities 2
• Paradoxically, Lactobacillus probiotics may help prevent recurrent UTIs by restoring normal vaginal flora 3, 4, 5
  • Lactobacillus rhamnosus GR1 and Lactobacillus reuteri RC14 are the most studied strains 4
  • Can be administered as vaginal suppositories or oral formulations 3, 6

Important Considerations

• ASB may actually protect against symptomatic UTI in some populations; treatment could disrupt this protective effect 1
• Unnecessary treatment of ASB contributes to antimicrobial resistance 1
• Distinguish between true infection and contamination/colonization before initiating treatment
• Consider local resistance patterns when selecting antimicrobial therapy

Monitoring and Follow-up

• Patients with symptomatic UTI should show clinical improvement within 24-48 hours of starting appropriate therapy 2
• Repeat urine culture is not necessary if symptoms resolve
• If symptoms persist despite treatment, consider urological evaluation, especially if hematuria is present 2

Remember that Lactobacillus in urine without symptoms rarely represents infection requiring treatment, and unnecessary antimicrobial use should be avoided to prevent resistance.